Dr Tony Holohan, Chief Medical Officer, was on leave when the new levels were drawn up
The Government's Living with Covid-19 system outlines five levels of response to the virus, each containing a set of measures.
So, what does Level 4 mean in terms of restrictions?
Social and family gatherings
In your home or garden
Own household only - no visitors.
Other settings outside your home or garden
No social or family gatherings should take place in other settings.
Up to 6 guests can attend a wedding ceremony and reception.
Organised indoor gatherings
These are controlled environments with a named event organiser, owner or manager.
For example: business, training events, conferences, events in theatres and cinemas or other arts events (excluding sport).
No organised indoor gatherings should take place.
Organised outdoor gatherings
These are controlled environments with a named event organiser, owner or manager. For example: outdoor Arts events, training events.
Gatherings of up to 15 people can take place.
Exercise and sporting events
Outdoors: Non contact training can take place but only in pods of up to 15.
Indoors: Individual training only. No exercise or dance classes can take place.
Matches and events
No matches or events to take place.
Exemption: Professional and elite sport/inter-county/horse-racing can take place behind closed doors.
Gyms, leisure centres and swimming pools
Gyms/leisure centres/swimming pools closed.
Services will be held online.
Places of worship remain open for private prayer.
Up to 25 mourners can attend.
Museums, galleries and other cultural attractions
All venues closed.
Online services available.
Bars, cafes and restaurants (including hotel restaurants and bars)
Take away food or delivery. No indoor dining.
Outdoor dining limited to a maximum of 15 patrons.
Outdoor seating only, limited to a maximum of 15 patrons.
Nightclubs, discos and casinos
Nightclubs, discos and casinos will remain closed.
Hotels and accommodation
Open but only for existing guests, and those with essential non-social and non-tourist purposes.
Retail and services (for example: hairdressers, beauticians, barbers)
Face coverings must be worn.
Essential retail and businesses that are primarily outdoors only can remain open. All other retail and personal services closed.
Only essential or other designated workers should go to work.
Domestic travel restrictions
Stay in your county (or other defined geographical area) apart from essential work, education and other essential purposes.
Schools, early learning and childcare services, adult and higher education
Schools and creches will remain open with protective measures.
Further, higher and adult education moves primarily online with appropriate protective measures in place for essential attendance on site.
Outdoor playgrounds, play areas and parks
All remain open with protective measures in place.
Face coverings must be worn.
Walk or cycle where possible.
Public transport capacity will be restricted to 25%.
Avoid public transport - essential workers and essential purposes only.
Over 70 and medically vulnerable individuals
Those aged over 70 years and over and the medically vulnerable should exercise judgement regarding the extent to which they engage with outhers and in activities outside home. Specific guidance will be issued.
Visiting long-term residential care facilities (nursing and care homes)
Suspended, aside from critical and compassionate circumstances.